1. Field of the Invention
This invention relates to an armor-penetrating tandem-projectile.
2. Description of the Related Art
Certain types of chemical energy (CE) warheads are formed by cone-shaped metallic liners which are later transformed into a metallic liquid jet by an explosive shaping charge carried on board the projectile. The CE warhead must be activated very near the target (about 1–2 meters) so that the formed metallic jet does not break up. Also, a spacer/spike in front of the liner provides a very short time delay needed to form the jet, when an impact fuse is mounted on the tip of that spacer spike. Alternatively, a proximity fuse may be used instead of the impact fuse if the intended target is moving (as in helicopters) or is relatively distant (4,000–5,000 meters) and a direct impact is less likely to happen. This last scenario is the actual incentive for the concept of multipurpose (MP) projectiles.
Anti-armor kinetic energy (KE) projectiles are long rods launched at high speed, causing damage due to their kinetic energy (mass and speed). Therefore, they are usually made of high density materials to increase the mass for a given volume.
U.S. Pat. No. 6,109,185 includes several tandem warhead configurations including KE-CE, CE-KE, KE-KE, or CE-CE arrangements. U.S. Pat. No. 4,102,271 discloses a KE-CE combination. U.S. Pat. No. 5,191,169 shows multiple EFP (explosively formed projectile) configurations. U.S. Pat. No. 5,744,746 shows a CE-CE tandem configuration. U.S. Pat. No. 4,497,253 shows a KE-KE configuration.
FIG. 1 illustrates a conventional multipurpose (MP) projectile 10, with its typical main components. Projectile 10 includes a metallic conical liner 12 which transforms into a liquid metallic jet after detonation. A conical nose windshield 14 reduces the drag and also provides a stand-off distance between the point of impact and the conical liner 12. A tail fin boom 16 is used to mount a stabilizing fin set piece 18. The tail fin boom 16 is usually screwed to the main body through threads 20 and to the fin set piece 18 through another set of threads 22.
FIG. 2 shows a conventional chemical energy (CE) projectile 30 also known as a HEAT (High Explosive Anti-Tank) projectile. It also has a metallic conical liner 32 and a front stand-off spacer 34, usually referred to as “the spike.” The solid tail fin boom 36 is also used to mount the stabilizing fin set piece 38. The tail fin boom 36 is attached to the main body of the projectile through threads 40, and a fin set piece 38 is attached to the tail fin boom 36 through another set of threads 42. In both FIGS. 1 and 2, the boom is usually solid (no internal holes or cavities) and only serves to carry the stabilizing fins.
FIG. 3 illustrates details of tail fin boom 50 of the MP projectile of FIG. 1, showing the threads 52 needed to connect to the main body of the projectile, as well as threads 54 needed to attach the tail set fins 56, which are part of the fin piece 57, to the tail fin boom.